60 



M. YOKOYAMA 



rian floras closely allied, nearly entire-margined leaves as Ginkgo in- 

 tegriuscula Hr. But this species he afterwards placed under G. 

 digitata as a variety only (Nachtr. p. 5), as Prof. Nathorst discovered 

 in the Oolite of Scarborough specimens which show passage forms 

 between these two species. 



Seems to have been very scarce in Japan. Loc. — Okamigô: 



40. Ginkgo ef. lepida Heer. 

 PL XIV, %. 10. 



Ginkgo lepida-Wccr, Beitr. z. Juraflora Ostsib. u. d. Amur]., 

 1876, p. 62, pi. XII, pi. VII, fig. 7. X T achtr., p. 17, pi. IV, fig. 7b, 

 9-12, pi. V, fig. In, 2, 3a, 4. 



A leaf which I figure here is not very complete. It is divided 

 into four lobes, and therefore furnished with three slits, the central of 

 which is the deepest, nearly reaching to the base of the leaf whence it 

 goes off into a petiole. The petiole however is unfortunately not 

 preserved. The other two slits are shallower. The lobes are narrow, 

 parallel-sided and acute at apex, as is seen from one of them. Veins 

 are parallel to the sides and about 6 in a lobe. Judging from these 

 characters, our plant is probably referable to the above named species 

 of Heer, which is distinguished from the very nearly related G. sibirica 

 Hr. in possessing narrower and especially acute lobes. 



Very rare. Loc. — Hakogase. 



41. Ginkgo sibiriea Heer. 



Ginkgo sibirica-G eyler, Ueber foss. Pflanz, a.d. Juraform. Japans, 

 p. 231, pi. XXXII, fig. 6. Heer, Beitr. z. Jnraflora Ostsib. u. d. 

 Amurl., 1876, p. 61, pi. VIT, fig. 6, IX, ob, XI, p. 116, pi. XX, fig. 3b,. 

 6c, XXII, 3, Beitr. 1878, p. 25, pi. VI, fig. 8a b. Nacht r. p. 16, pi. 

 IV, fig. 13, V, 5-8. Schmalhausen, Beitr. z. Jnraflora Russh, p. 34. 



